Black Locust
Robinia pseudoacacia • Hardwood
Grain Pattern
Usually straight but sometimes slightly interlocked. The end grain shows prominent, closely spaced earlywood pores filled with tyloses, creating distinct growth rings and a coarse texture.
Color Description
Heartwood is a pale yellowish brown to greenish or golden brown, as seen in the freshly cut sample. It darkens to a russet brown with age. Sapwood is yellowish-white and clearly demarcated from heartwood.
Hardness Rating
1,700 lbf (Hard to Very Hard classification)
Durability Rating
Very Durable. Exceptional resistance to rot and decay; it is widely considered one of the most durable woods in North America, outperforming most species in ground contact.
Common Uses
Fence posts, boatbuilding, exterior furniture, heavy decking, mine timbers, railroad ties, and tool handles.
Geographic Origin
Native to the Appalachian Mountains and the Ozark Plateau of the United States; widely naturalized across North America, Europe, and Asia.
Market Value & Sustainability
Estimated Market Value
$5.00 - $8.00 per board foot depending on region and drying condition.
Wood Age Estimate
The sample appears relatively fresh or recently cut based on the brightness of the yellow-green hues, likely processed within the last 12 months. Growth rings suggest a tree that was at least 20-30 years old.
Sustainability Status
Not listed in the CITES Appendices or on the IUCN Red List; generally considered sustainable and even invasive in some regions due to fast growth.
Workability
Difficult to work due to its high density and hardness. It has a high blunting effect on tool edges. Turns well but may produce tearout if grain is interlocked. Glues and finishes well.
Notable Features
Often fluoresces under UV light (appearing bright yellow/green). Contains high amounts of tyloses which block the pores, making it extremely water-resistant. Known for its high strength-to-weight ratio.
Finish Recommendations
Penetrating oils or marine-grade spar varnishes for outdoor use to preserve color; polyurethane or lacquer for indoor furniture. It takes a polish very well.
Identification Confidence
High. The distinctive golden-yellow/greenish hue of the heartwood, the massive presence of tyloses in the large earlywood pores visible in the end grain, and the thick, craggy bark fragment are classic indicators of Robinia pseudoacacia.